Restriction fragment analysis of ‘null’ forms at the Gli-1 loci of bread and durum wheats

Summary Wheat accessions lacking some of the - and -gliadin components encoded by the Gli-1 loci on the short arm of chromosome 1D in bread wheat and chromosome 1A in durum wheat were studied by two-dimensional polyacrylamide gel electrophoresis and restriction fragment analysis. Digested genomic DNAs of normal and null forms were probed with a cDNA clone related to -/-gliadins and with a genomic clone encoding an LMW subunit of glutenin. The hybridisation patterns with the -/-gliadin probe were similar to those of cvs Chinese Spring and Langdon used as standards for bread and durum wheats, respectively, but several restriction fragments located on the 1D chromosome of bread wheat and the 1A chromosome of durum wheat were absent in the null forms. In addition, specific LMW glutenin fragments encoded by the same chromosomes were also absent in the null forms, suggesting that simultaneous deletions of blocks of genes for both -/-gliadins and LMW glutenins had occurred. Comparisons of the protein and RFLP patterns enabled some proteins to be mapped to specific restriction fragments.     

Don't Blame the ‘Bio’ — Blame the ‘Ethics’: Varieties of (bio) ethics and the challenge of pluralism

We tend to think that the difficulties in bioethics spring from the novel and alarming issues that arise due to discoveries in the new biosciences and biotechnologies. But many of the crucial difficulties in bioethics arise from the assumption we make about ethics. This paper offers a brief overview of bioethics, and relates ethical 'principlism' to 'ethical fundamentalism.' It then reviews some alternative approaches that have emerged during the second phase of bioethics and argues for a neo-Aristotelian approach. Misconceptions about ethical principles and ethical reasoning not only distort our views of the business of bioethics, but they also prevent us from facing up to the formidable problems posed by ethical pluralism in so-called liberal societies.     

Commensal ‘trail of bread crumbs’ provide pathogens with a map to the intestinal landscape

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Observations on the biology of Leuciscus ‘svallize’ in the Kremasta reservoir (Greece)

The age, growth, feeding habits and reproductive biology of Leuciscus svallize in artificial lake Kremasta (Greece), are described. There is a considerable similarity in the feeding and reproductive characteristics between L. svallize and L. cephalus and also a similarity in the life span, growth patterns and age of maturation between L. svallize and some southern L. cephalus populations, which may suggest similar responses of closely related taxa to similar conditions.     

Immature stages of Curculionidae: the ‘rat-tailed’ larva and the pupa of Notonesius aucklandicus (Phrynixinae)

Abstract

The larva and pupa of Notonesius aucklandicus Kuschel, living in saturated peat soil on the Auckland Islands, some 500 km south of New Zealand, are described and figured. The ‘rat-tail’ type of aquatic adaptation in the larva appears to be unique among Coleoptera, although an evolutionary progression towards it can be traced among Indian weevils.     

‘We all eat the same bread’: the roots and limits of cosmopolitan bridging ties developed by Romanians in London

This paper investigates the social ties forged by Romanians in London with migrants of different origins in work and non-work contexts to offer a more nuanced view of ‘bridging’ social ties and related discussions of ‘everyday’ cosmopolitanism. Contrary to the overemphasis on ethnic ties seen as a form of bonding in migration research, the paper shows how Romanians bridge informally with many other migrants based on shared ‘non-native’ status. Alongside non-ethnically marked commonalities, ethnicity emerges as an important ingredient of cosmopolitan socialization, yet without necessarily signalling coexisting ethnic identities, as commonly assumed. Romanians' experiences further show that despite providing significant social and cultural capital, bridging ties with migrants, rather than natives, rarely accrue effective resources for social mobility. The findings suggest the need to disaggregate and qualify current understandings of ‘bridging’ social ties usually depicted in positive terms and uniformly as cross-ethnic relationships, or only linked with the ‘mainstream’ population.     

On the ‘transmission sense of information’

In order to illuminate the role of information in biology, Bergstrom and Rosvall (Biol Philos 26:159–176, 2011a; Biol Philos 26:195–200, 2011b) propose a ‘transmission sense of information’ which builds on Shannon’s theory. At the core of the transmission sense is an appeal to the reduction in uncertainty in receivers and to etiological function. I explore several ways of cashing out uncertainty reduction as well as the consequences of appealing to function.     

Making sense of ‘mixture’: states and the classification of ‘mixed’ people

Caribbean diaspora intellectuals have contributed significantly to African-American political struggles over the years, despite arguments by some African-American intellectuals about what they discern as West Indian negativism, extremism, and divisiveness in American political life. This essay examines the legacy of a representative sample of diasporic Caribbean intellectuals since the time of the Harlem Renaissance in the 1920s and culminating in the 1970s, notably, Garvey, members of the African Blood Brotherhood [ABB], C.L.R. James, and Walter Rodney, to demonstrate the phenomenal ideological vision, organizational capability, and political activism they have brought into fostering solidarity with African Americans in the struggle for fundamental change. The focus here is on their respective contributions to the debate on the relationship between class and race in America and the black diaspora generally, which has helped to shape the form, and orient the direction of African-American and Caribbean diasporic struggles for the better part of the twentieth century.     

On the correct use of ‘data’

Acknowledgement  Thanks are due to Drs. Paul Johnston (P.Johnston@ exeter.ac.uk) and E. William Beese (ebeese@t-online.de) for kindly providing dictionary definitions and for sharing their thoughts about the correct use of ‘data’.     

Ultrastructure of the dendritic outer segments of sensory cells in poreless (‘no-pore’) sensilla of insects

Summary Poreless sensilla with inflexible sockets in insects presumably house hygro- and thermoreceptors (type-1, type-2 receptors). The dendritic outer segments of these receptor cells were studied mainly in cryofixed antennae of two species of moth (Antheraea pernyi, A. polyphemus) and one beetle (Aleochara curtula). As a rule two type-1 receptor cells are present. Their dendritic outer segments do not branch. They project into the distal cuticular parts of the sensillum and are in close contact with its four-layered wall. The segments differ in shape and microtubule density. As well, in A. curtula, the microtubules are interconnected by electron-dense material for some distance, thus forming a tubular body-like structure of 1.3 m length. The dendritic outer segment of the single type-2 receptor cell is branched and lamellated. Its lamellae are connected by structures similar to septate junctions, which occupy about 70% of the total surface of the lamellated portion of the dendrite. In tangential sections, the septa appear as parallel strands approximately perpendicular to the long axis of the dendritic segment. The structure of type-1 receptors is discussed with regard to the hypothesis for a mechano-electrical transduction. The possible functions of lamellation and junctional connections in type-2 receptors are discussed.Supported by the Deutsche Forschungsgemeinschaft (SFB 4/G1)     

Functional organization of the skin of the ‘Green-puffer fish’Tetraodon fluviatilis (Ham.-Buch.) (Tetraodontidae,Pisces)

Summary The present study concerns the functional organization of the skin ofTetraodon fluviatilis. The epidermis consists of five different types of cells — the flask-shaped mucous cells, the eosinophilic granular cells, the sacciform granulated cells, the vesicle containing granulated cells, and the polygonal cells. A thin noncellular layer, the cuticle found on the surface of the skin, is probably secreted from the polygonal cells in the outermost layer of the epidermis. A,well-defined lymphatic plexus exists between the cells of the basal layer.Numerous triradiate calcareous spines are embedded within elastic connective tissue pockets in the thick dermis. These pockets are filled with an amorphous, acellular, PAS positive material, and are richly supplied with fine blood capillaries. A histomorphologic basis for the erection of the spines and various structural modifications in the skin facilitating its enormous stretching under inflated conditions of the fish are discussed.Abbreviations Used BCA blood capillary - BM basement membrane - BC basal cell - BL basal layer - CFB collagen fiber bundle - CTB connective tissue band - DER dermis - EGC eosinophilic granular cell - EPD epidermis - FB fibroblasts - FC fat cell - L lymphocyte - LS lymphatic space - MC mucous cell - ML middle layer - MUS muscle - MYS myocommata - NV nerve - OL outermost layer - PCB black pigment cell - PCY yellow pigment cell - PEC polygonal epidermal cell - SCT subcutis - SGC sacciform granulated cell - SP spine - STC stratum compactum - STL stratum laxum - VGC vesicle containing granulated cell - VS vertical strand This investigation was supported by a research grant No. 38(131)/72-GAU-II from the Council of Scientific and Industrial Research and a financial assistance grant for teachers No. F. 6(4626) 72-(SF-1), from the University Grants Commission, Government of India, New Delhi.     

Phylogenetic Relationships of the Triassic Archaeosemionotus Deecke (Halecomorphi,Ionoscopiformes) from the ‘Perledo Fauna’

The lagerstätten in the Monte San Giorgio have provided excellent fossils representing one of the most important windows to the marine life during the Triassic. Among these fossils, fishes are abundant and extraordinarily well preserved. Most of these fishes represent extinct lineages and were difficult to understand and classify during the early years after discovery. These difficulties usually led to a mixture of species under the same taxonomic name. This is the case of fishes referred to the genus Archaeosemionotus. The name bearing type of A. connectens, the type species of this genus, represents a basal halecomorph, but most other fishes referred to this genus represent basal ginglymodians. Therefore, we conducted this study to clarify the taxonomic status and phylogenetic relationships of A. connectens, which is a member of the family Furidae (Halecomorphi, Ionoscopiformes) representing the second cladistically supported evidence of ionoscopiforms in the Triassic and it is thus one of the two oldest reliable records of this group. Ionoscopiforms have a long stratigraphic range, though their fossil record is rather patchy. In our analysis, the sister taxon of Archaeosemionotus is Robustichthys from the Anisian of China, and they together form a clade with Furo, which is known from several localities ranging from the Early to the Late Jurassic. Other ionoscopiforms are so far known from the Kimmeridgian to the Albian and it is thus evident that recent efforts have concentrated on the later history of the group (Late Jurassic to Cretaceous). The phylogenetic relationships obtained for the Ionoscopiformes do not show a clear palaeobiogeographic pattern, but give important new insights into the origin, divergence date and early history of this clade.     

The (dis)similarities of white racial identities: the conceptual framework of ‘hegemonic whiteness’

This article examines the processes of white racial identity formation in the United States via an examination of a white nationalist organization and a white antiracist organization. Findings indicate that the construction of white racial identity in both groups is based on the reproduction of various racist and essentialist ideologies. The realization that there is a shared ‘groupness’ to outwardly different white identities has the potential to destabilize the recent trend that over-emphasizes white heterogeneity at the expense of discussion of power, racism and discrimination. As a resolution to this analytic dilemma, this article advances a conceptual framework entitled ‘hegemonic whiteness’. White identity formation is thereby understood as a cultural process in which (1) racist, reactionary and essentialist ideologies are used to demarcate inter-racial boundaries, and (2) performances of white racial identity that fail to meet those ideals are marginalized and stigmatized, thereby creating intra-racial distinctions within the category ‘white’.     

Ultrastructural localization of ‘anixiopsin’: a lectin of the fungus Anixiopsis stercoraria (Hansen) Hansen

In order to localize the anixiopsin, a lectin of the keratinolytic fungus Anixiopsis stercoraria, the authors used a monospecific antiserum prepared by immunization of rabbits with their own erythrocytes coated in vitro with anixiopsin. In light and scanning electron microscopies, lectinic sites were visualized by means of latex microspheres sensitized with anti-rabbit IgG antibodies. In transmission electron microscopy using the IgG fraction of the rabbit anti-anixiopsin immune sera and protein A-gold, anixiopsin seemed mainly present on the outermost cell wall layer of the ascospores, in a pseudomembraneous structure dense to electrons. Implications of these results on physical and biological properties of the lectin are discussed.